Modern motor vehicles may be equipped with an electric power-generating device that operates with a fuel cell independently of the engine to supply the electric power needed by the vehicle. To do so, a hydrogen-containing fuel gas is produced as a reformate with the help of a reformer from the particular fuel supplied to it, such as gasoline or diesel. This reformate or fuel gas may then be utilized to generate electric current in a fuel cell together with a gaseous oxidizer containing oxygen, usually air. The fuel cell therefore contains at least one electrolyte plate, with the fuel gas flowing past the anode side and the oxidizer gas flowing past the cathode side. Chemical reactions occur in both the fuel gas and the oxidizer gas, forming the respective reaction products. Usually not all the hydrogen in the fuel gas is reacted, so a hydrogen-product gas mixture comes out of the fuel cell on the anode side. The situation is similar with the oxidizer mixture because, as a rule, not all of the oxygen can be reacted there either. Consequently, an oxygen-product gas mixture comes out of the fuel cell on the cathode side. From the standpoint of strict limits on pollutant emissions, it is not desirable to discharge hydrogen into the environment.
The present invention addresses the problem of providing a method of reducing pollution for a fuel cell.
This problem is solved according to this invention through the objects of the independent claims. Advantageous embodiments are the object of the dependent claims.